I don't want to speak for you, so I can't say to what degree I agree or disagree.

Here's my little train of thought the racial politics of this thing:

I don't think the setting and peoples represented inherently made me like or dislike the movie any more than a different setting.

It was nice to see a world not represented very often, but I cannot comment on the factual basis for sets, costumes, or actions.

I did think a wide range of characters were shown, so while I do believe it is possible it presented broad stereotypes I thought a good job was done of individualizing everyone.

If this movie was set in Middle Ages Europe I still think I would like it.

At the same time, Gibson has sort of already made that movie. He clearly likes historical pieces, and he's now been to Middle Ages Scotland, turn of the millennium Middle East, and 16th/17th century South America. (I know it was shot in Mexico, but I thought it was set in the continental south.)

Now, whether or not it is factually correct is something I will gladly learn more about, but I will reserve a moral judgment on it till later. I am a-okay with movies changing facts to serve the film, but if things were done out of laziness I can see it from your side.